Morphographic study of some dispersed Trilete Miospores (Sub-Infraturma-Varitrileti) from the Lower Gondwana of India

Abstract

The sub-infraturma Varitrileti includes such trilete miospores which exhibit differential distribution of ornament as well as characteristic folds associated with the trilete rays. In the course of time, a number of genera were accommodated in this group and their stratigraphic significance was also indicated. The present investigation suggests that six genera could be delimited in this group, viz., Microbaculispora, Microfoveolatispora, Didecitriletes, Lacinitriletes, Brevitriletes, and Imparitriletes gen. nov. In the present work, attempts have been made to circumscribe the species of each genus on the basis of quantitative characters determined statistically after studying a number of specimens as well as the types. In all, 19 species have been recognized and described in detail. The distribution pattern of the species in each genus of this group has been ascertained on the basis of quantitative analysis of some well-dated sequences which collectively represent the Lower Gondwana formations.